Add more info to Sfx stat

Add additional information about remaining notes

Author: elgopher

audio/audio.go

@@ -68,11 +68,16 @@ func GetStat() Stat {
 var system System = &Synthesizer{}
 
 type Stat struct {
-	Sfx           [4]int // -1 means no sfx on channel
-	Note          [4]int // -1 means no sfx on channel. Not implemented yet.
-	Pattern       int    // currently played music pattern. Not implemented yet.
-	PatternsCount int    // the number of music patterns played since the most recent call to Music(). Not implemented yet.
-	TicksCount    int    // the number of ticks (notes or rests) played on the current pattern. Not implemented yet.
+	Sfx           [4]SfxStat
+	Pattern       int // currently played music pattern. Not implemented yet.
+	PatternsCount int // the number of music patterns played since the most recent call to Music(). Not implemented yet.
+	TicksCount    int // the number of ticks (notes or rests) played on the current pattern. Not implemented yet.
+}
+
+type SfxStat struct {
+	SfxNo     int // -1 means no sfx on channel
+	Note      int // current note in sfx
+	Remaining int // number of remaining notes in sfx. -1 if loop
 }
 
 type SoundEffect struct {
@@ -101,6 +106,18 @@ func (s SoundEffect) noteAt(no int) Note {
 	return note
 }
 
+func (s SoundEffect) hasLoop() bool {
+	return s.LoopStop > s.LoopStart
+}
+
+func (s SoundEffect) hasLength() bool {
+	return s.LoopStart > s.LoopStop
+}
+
+func (s SoundEffect) length() int {
+	return int(s.LoopStart - s.LoopStop)
+}
+
 type Note struct {
 	Pitch      Pitch      // 0-63
 	Instrument Instrument // 0-15

audio/synth.go

@@ -115,6 +115,12 @@ func (s *Synthesizer) Play(sfxNo, ch, offset, length int) {
 	s.channels[ch].sfxNo = sfxNo
 	s.channels[ch].frame = 0
 	s.channels[ch].noteNo = offset
+	if length <= 0 && sfx.LoopStop <= sfx.LoopStart {
+		length = 32
+	}
+	if length > 32 {
+		length = 32
+	}
 	s.channels[ch].notesToGo = length
 	s.channels[ch].loopingDisabled = false
 
@@ -183,14 +189,29 @@ func (s *Synthesizer) Music(patterNo int, fadeMs int, channelMask byte) {
 }
 
 func (s *Synthesizer) Stat() Stat {
-	fmt.Println("Stat is not implemented yet. Sorry...")
+	fmt.Println("Stat is not fully implemented yet. Sorry...")
 
 	stat := Stat{}
 	for i, c := range s.channels {
 		if c.playing {
-			stat.Sfx[i] = c.sfxNo
+			sfxStat := SfxStat{
+				SfxNo:     c.sfxNo,
+				Note:      c.noteNo,
+				Remaining: c.notesToGo,
+			}
+			sfx := s.GetSfx(c.sfxNo)
+			if sfx.hasLoop() {
+				sfxStat.Remaining = -1
+			} else if sfx.hasLength() {
+				sfxStat.Remaining = minInt(sfx.length(), c.notesToGo)
+			}
+			stat.Sfx[i] = sfxStat
 		} else {
-			stat.Sfx[i] = -1
+			stat.Sfx[i] = SfxStat{
+				SfxNo:     -1,
+				Note:      -1,
+				Remaining: 0,
+			}
 		}
 	}
 	return stat

audio/synth_test.go

@@ -353,6 +353,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 				assertSilence(t, buffer)
 
 				t.Run("and next note with max volume should be played", func(t *testing.T) {
+					assert.Equal(t, 2, synth.Stat().Sfx[0].Note)
 					synth.ReadSamples(buffer)
 					assertNotSilence(t, buffer)
 				})
@@ -415,7 +416,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 		synth.Play(sfxNo, -1, 0, 1)
 		// then
 		stat := synth.Stat()
-		assert.Equal(t, sfxNo, stat.Sfx[3])
+		assert.Equal(t, sfxNo, stat.Sfx[3].SfxNo)
 		assertNotSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 	})
 
@@ -435,7 +436,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 		synth.Play(sfxNo, -1, 0, 1)
 		// then
 		stat := synth.Stat()
-		assert.Equal(t, sfxNo, stat.Sfx[3])
+		assert.Equal(t, sfxNo, stat.Sfx[3].SfxNo)
 		assertNotSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 	})
 
@@ -451,8 +452,8 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 		synth.Play(0, 1, 0, 1)
 		// then
 		stat := synth.Stat()
-		assert.Equal(t, -1, stat.Sfx[0])
-		assert.Equal(t, 0, stat.Sfx[1])
+		assert.Equal(t, -1, stat.Sfx[0].SfxNo)
+		assert.Equal(t, 0, stat.Sfx[1].SfxNo)
 		// and
 		signal := readSamples(synth, durationOfNoteWhenSpeedIsOne)
 		expectedSignal := generateSamples(e, durationOfNoteWhenSpeedIsOne)
@@ -477,7 +478,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 		synth.Stop(-1)
 		// then
 		stat := synth.Stat()
-		assert.Equal(t, -1, stat.Sfx[0])
+		assert.Equal(t, -1, stat.Sfx[0].SfxNo)
 		// and
 		assertSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 	})
@@ -500,7 +501,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 		synth.StopChan(-1)
 		// then
 		stat := synth.Stat()
-		assert.Equal(t, -1, stat.Sfx[0])
+		assert.Equal(t, -1, stat.Sfx[0].SfxNo)
 		// and
 		assertSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 	})
@@ -522,7 +523,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 				synth.Play(0, ch, 0, 1)
 				// then
 				stat := synth.Stat()
-				assert.Equal(t, 0, stat.Sfx[0])
+				assert.Equal(t, 0, stat.Sfx[0].SfxNo)
 				// and
 				assertNotSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 			})
@@ -546,7 +547,7 @@ func TestSynthesizer_PlayStop(t *testing.T) {
 				synth.Play(sfxNo, 0, 0, 1)
 				// then
 				stat := synth.Stat()
-				assert.Equal(t, 0, stat.Sfx[0])
+				assert.Equal(t, 0, stat.Sfx[0].SfxNo)
 				// and
 				assertNotSilence(t, readSamples(synth, durationOfNoteWhenSpeedIsOne))
 			})
@@ -928,6 +929,107 @@ func sfxLengthTest(t *testing.T) {
 	})
 }
 
+func TestSynthesizer_Stat(t *testing.T) {
+	t.Run("should return sfx stat when no sfx were played", func(t *testing.T) {
+		var synth audio.Synthesizer
+		expected := audio.SfxStat{
+			SfxNo:     -1,
+			Note:      -1,
+			Remaining: 0,
+		}
+		stat := synth.Stat()
+		for i := 0; i < maxChannels; i++ {
+			assert.Equal(t, expected, stat.Sfx[i])
+		}
+	})
+
+	t.Run("should return issued note", func(t *testing.T) {
+		for note := 0; note < 2; note++ {
+			var synth audio.Synthesizer
+			synth.Play(0, 0, note, 0)
+			assert.Equal(t, note, synth.Stat().Sfx[0].Note)
+		}
+	})
+
+	t.Run("should return issued remaining notes", func(t *testing.T) {
+		for length := 1; length < 3; length++ {
+			var synth audio.Synthesizer
+			synth.Play(0, 0, 0, length)
+			assert.Equal(t, length, synth.Stat().Sfx[0].Remaining)
+		}
+	})
+
+	t.Run("should return 32 when issued length was 0", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.Play(0, 0, 0, 0)
+		assert.Equal(t, 32, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return -1 when sfx has loop", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.SetSfx(0, audio.SoundEffect{
+			LoopStart: 0,
+			LoopStop:  1,
+		})
+		synth.Play(0, 0, 0, 0)
+		assert.Equal(t, -1, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return -1 when sfx was updated after played", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.Play(0, 0, 0, 0)
+		synth.SetSfx(0, audio.SoundEffect{
+			LoopStart: 0,
+			LoopStop:  1,
+		})
+		assert.Equal(t, -1, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return length when sfx.LoopStart > sfx.LoopStop", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.SetSfx(0, audio.SoundEffect{
+			LoopStart: 1, // len=1
+			LoopStop:  0,
+		})
+		synth.Play(0, 0, 0, 0)
+		assert.Equal(t, 1, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return min length when sfx.LoopStart > sfx.LoopStop", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.SetSfx(0, audio.SoundEffect{
+			LoopStart: 3, // len=3
+			LoopStop:  0,
+		})
+		synth.Play(0, 0, 0, 2) // len=2
+		assert.Equal(t, 2, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return remaining notes after one note was played", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.Play(0, 0, 0, 2)
+		readSamples(&synth, durationOfNoteWhenSpeedIsOne)
+		assert.Equal(t, 1, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return 32 when length higher than 32", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.Play(0, 0, 0, 33)
+		assert.Equal(t, 32, synth.Stat().Sfx[0].Remaining)
+	})
+
+	t.Run("should return remaining notes when sfx has length (loop start > loop stop) and one was played", func(t *testing.T) {
+		var synth audio.Synthesizer
+		synth.SetSfx(0, audio.SoundEffect{
+			LoopStart: 3, // len=3
+			LoopStop:  0,
+		})
+		synth.Play(0, 0, 0, 2)
+		readSamples(&synth, durationOfNoteWhenSpeedIsOne)
+		assert.Equal(t, 1, synth.Stat().Sfx[0].Remaining)
+	})
+}
+
 func readSamples(synth *audio.Synthesizer, size int) []float64 {
 	buffer := make([]float64, size)
 	synth.ReadSamples(buffer)

ebitengine/audio.go

@@ -57,8 +57,12 @@ func startAudio() (stop func(), ready <-chan struct{}, _ error) {
 			audioSystem: synth,
 			readSamples: liveReader.ReadSamples,
 		}
+		stat := audio.GetStat()
 		audio.SetSystem(audioSystem) // make audio system concurrency-safe
 		audio.Sync()
+		for channel, sfx := range stat.Sfx {
+			audioSystem.Play(sfx.SfxNo, channel, sfx.Note, sfx.Remaining)
+		}
 		AudioStream = audioSystem
 	}
 

examples/audio/audio.go

@@ -17,6 +17,8 @@ func main() {
 
 	sfxNote0 := &audio.Sfx[0].Notes[0]
 
+	audio.Play(0, 0, 0, 0)
+
 	pi.Update = func() {
 		if pi.Btnp(pi.X) {
 			audio.Play(0, 0, 0, 0)